The invention set forth in this specification pertains to new and improved screed extensions of use with machines for spreading pulverulent material such as machines utilized in spreading an asphalt-rock composition utilized in creating so-called "blacktop" pavement.
For many years it has been common to construct paving machines as are indicated in the preceding paragraph utilizing a mold board at the back of an area where pulverulent material is distributed. As a machine as indicated moves in a forward direction the mold board acts to smooth and level off this pulverulent material. Occasionally it is necessary and/or desirable to use a paving machine to distribute and level off such material beyond an end of a mold board. As a consequence of the recognition of this need so-called "screed extensions" have been developed for use with paving machines as described.
Such screed extensions have normally utilized a strike-off plate mounted in front of the mold board adjacent to the end of the mold board in a manner permitting such a plate to be moved either outwardly from or inwardly toward the mold board as desired as a machine for spreading pulverulent material of the type indicated is used. While certain prior screed extension devices of the type indicated are considered to be quite utilitarian and desirable it is considered that there is a need for screed extensions devices in which a hydraulic mechanism for moving a strike-off plate is located in such a location that the heat of any pulverulent material processed will not affect the operation of the hydraulic mechanism. Further, it is considered that there is a need for screed extensions having a smaller cross-sectional dimension than prior screed extensions so as to avoid any possibility of the extension interfering with the operation of the machine. It is also considered that there is a need for new and improved screed extension apparatus which may be easily and conveniently constructed at a comparatively nominal cost and which are capable of being utilized for prolonged periods with minimum amounts of maintenance.